Preparation and use of textile threads



Patented Aug. 10, 1937 UNITED STATES PATENT OFFICE PREPARATION AND USE OF TEXTILE THREADS of Delaware No Drawing.

Application June 8, 1936,

Serial No. 84,162

6 Claims.

This invention relates to the manufacture of crepe threads and filaments of cellulose acetate or other organic derivatives of cellulose and to the production of fabrics therefrom where an aid,

5 containing a mixture or solution of a plasticizer in oil for enhancing the crepe and textile properties is incorporated withyarns prior to forming them into crepe threads.

This application is a continuation in part of our application S. No. 22,173 filed May 18, 1935. An object of this invention is the economic and expeditious production of threads containing organic derivatives of cellulose, which have a high degree of crepe suitable for the production of crepe fabrics. A further object of this invention is the treatment of yarns and the twisting of the same to a high degree of twist in such a manner as to produce fabrics having a uniform creping property. A further object of this invention is the production of crepe threads that shrink and buckle in a very short period of time when immersed in a heated creping bath. Other objects of the invention will appear from the following detailed description.

In accordance with the present invention, highly twisted crepe threads of filaments of organic derivatives of cellulose are produced from threads of filaments of organic derivatives -of cellulose, which have incorporated therewith a mixture or solution of dibutyl phthalate or similar plasticizer and a vegetable oil such as olive oil or castor oil, by crepe twisting and during the insertion of the crepe twist steaming the threads. It is of great advantage to have moisture present during the steaming. Thus, during the twisting operation steam may be applied to the traveling yarn over at least a portion of that part of its track in which twisting takes place. At least some of the twist is inserted in the thread while the thread is under the influence of steam.

This invention is of especial value and will be more particularly described in connection with the production of crepe threads or filaments of cellulose acetate.

By incorporating a mixture or solution of dibutyl phthalate or similar plasticizer with castor oil, olive oil or other similar vegetable oil with the filaments of cellulose acetate, it has been found possible to produce crepe threads which yield fabrics exhibiting crepe effects of an excellence hitherto unattained with cellulose acetate crepe threads. Moreover, with this new process there may be produced cellulose acetate crepe threads which have an average strength very much greater than that of cellulose acetate crepe threads produced by a simple twisting operation without the aid of plasticizers and oil during the twisting and steam treatment. Further, apart from the great advantage-of a strong resultant thread, the twisting operation itself is greatly 5 facilitated in that twisting may be satisfactorily accomplished under conditions of twist and spindle speed which, in the absence of the plasticizer and oil, would give rise to frequent thread breakage and render impossible the insertion of the desired twist or atleast lead to a very weak and useless thread. By employing dibutyl phthalate and a vegetable 011 there is produced a more uniform,and more quick action of the steam upon the thread being twisted.

By incorporating a mixture or solution of a plasticizer and an oil withzthe filaments of cellulose acetate, not only are the threads given enhanced properties for the textile operations and a more uniform crepe pebble produced in the fabric but the speed of shrinkage in the boil-01f or creping bath is greatly increased. This is especially true when employing a plasticizer of the dibutyl phthalate type or a-plasticizer having the same properties as dibutyl phthalate in regard to plasticizing action on cellulose acetate, solubility in water, miscibility in vegetable oils, etc. The plasticizer may be mixed with or dissolved in the oil in amounts up to- 80% on the weight of the oil. This mixture or solution may then be incorporated with the filaments 'or threads of cellulose acetate by adding same to the spinning solution'or dope from which the filaments constituting the thread or yarn are formed. Thus, up to 10% by weight of a plasticizer oil creping aid or agent may be added to a solution of an organic derivative of cellulose in a volatile solvent and the same extruded through orifices of suitable diameter to form the type of yarn desired. Either the wet or dry method of spinning may be employed. When the creping aid or agent is incorporated in the spinning solution it is not necessary that the same contain a preponderance of oil, but a small amount is sufficient, say from 5 to 40% on the weight of the creping agent or aid. By another modification the plasticizer mixed with or dissolved im an oil may be incorporated with the yarn by applying same as acoating to the yarn after thefiyam has been formed. The plasticizer-oil creping aid may be applied to the yarn as a coating at the metier i as the yarns are formed or during any subsequent winding operation prior to imparting twist thereto. The creping agent or aid may consist of from 5 to parts or more of dibutyl phthalate or similar plasticizer and 95 to 20 parts of a vegetable oil such as olive oil, castor oil and the like. In place of or in conjunction with the vegetable oil, other oils may be employed such as mineral oils, animals oils or mixtures of the various oils. Although any proportion of plasticizer to oil may be employed, we prefer to employ from 40 to 60 parts of plasticizer to 60 to 40 parts of oil.

The creping agent or aid containing the plasticizer and oil may be applied to the yarn, while 'the yarn is in a stage of travel as during its formation or during a winding operation, by causing the yarn to contact with a wick or roller that dips into the mixture or solution containing the same, or by any other suitable furnishing device or method. Any desired amount of creping agent or aid may be applied to the yarn prior to steaming and twisting. The creping agent or aid may be applied to the yarn which already has a coating of a lubricant thereon which lubricant may be a vegetable oil, sulphonated naphthene and/or mineral oil. It is of advantage, however, to maintain the finishes on the yarn to as small a percent as possible without running into difliculties in the textile operations. When employing as a creping agent or aid an agent consisting of 50/50 dibutyl phthalate-castor oil, we have found that from 1% to 3% of this finish based on the weight of the yarn produces excellent results. 1% to 3% is found to be of advantage, a greater percent, say up to 10% or more, may be employed.

The threads may consist of substantially continuous filaments of cellulose acetate or they may contain discontinuous filaments of cellulose acetate, the length of which may vary within wide limits. For example, the threads may be those spun from a mass of discontinuous filaments or those prepared in the manner described in copending U. S. application S. No. 726,275 filed May 18, 1934. The threads .may contain besides organic derivatives of cellulose, other textile filaments or fibers. Further the threads may be formed from a bundle of substantially continuous filaments or by doubling two or more yarns. The threads may also be formed from fibers by cotton and woolen methods of forming yarns.

If desired; the filaments of the threads may contain water-insoluble compounds, such as compounds of pigment-like character, in such form as materially to modify the luster of the filaments (e. g. barium sulphate or titanium dioxide), or loading metal compounds, for example, tin compounds.

In carrying out the new process, twisting may be efiected on a device of the kind in which the thread is drawn off over the end of a rotating package through a guide fixed preferably substantially in line with the axis of rotation of the package and is thereafter wound on a bobbin or the like, the thread being passed, on its way from the, guide to the bobbin, through steam. In this way the thread is subjected to the action of the steam during the actual application of a substantial amount of the twist, or to the action of both steam and moisture if it is passed through steam under such conditions that moisture is present.

On the other hand, any other suitable crepe twisting device may be employed in conjunction with steaming. For example, a ring twister may be used for the crepe twisting of thread consisting of discontinuous cellulose acetate filaments, or by other suitable devices. As examples of such devices may be mentioned flyers and the floating ring device described in British Patent No. 304,- 806 to British Celanese Limited and Others,

Although Steaming may conveniently be efiected by allowing the thread to pass through a suitable chamber supplied with steam preferably under such conditions that moisture is present. The chamber is provided with small holes, top and bottom, to permit passage of the thread, and also with a steam inlet. If desired, a single steam chamber may be arranged to serve a number of twisting devices, being provided with inlet and outlet holes for the thread of each device. Such an apparatus may conveniently consist of a horizontal pipe mounted over a row of twisting de vices and provided with eyes of porcelain, stainless steel, or other suitable material at appropriate points on top and bottom for the entrance and exit of the threads. The diameter of the pipe may be sufiicient to afiord the thread the requisite length of travel in the steam. Alternatively, a pipe having a smaller diameter may be used, in which case the pipe may be provided with hollow nipples communicating therewith and through which the yarn passes, the

nipples being of suflicient length to provide, to-

gether with the diameter of the pipe, the requisite length of travel in the steam.

The presence of the desired moisture may be assured by supplying wet steam to the steaming device and/or by arranging for the condensation of steam to supply the requisite amount of moisture. Wet steam may be conveniently produced by passing steam through water at suitable velocity, for instance, small traps for condensed water may be provided at suitable intervals in the steaming chamber and steam injected therethrough by means of small pipes or orifices. Another method of ensuring the presence of moisture is to wet the thread with water. For example, the bobbins of thread may be wetted before the twisting operation or, better, water may be applied to the thread by means of a wick or other device after the thread leaves the spindle and prior to its entering the steaming device.

Steam at slightly above atmospheric pressure,

. or at a pressure of 1 to 2 millimeters of water, is-

most conveniently employed. If desired, however, the steaming may be efiected with steam at any desired super-atmospheric pressures, e. g. steam at 10-25 lbs. per square inch.

A steaming treatment of relatively short duration such as may be secured by passing the yarn at a speed of from 2 to 10 metres per minute through say from 1 inch to six inches of steam has been found to give satisfactory results.

lengthier treatments may, however, be employed,

for example, the yarn may be passed at the said speeds through 6 inches to 12 inches or more of steam.

The cellulose acetate filaments of the threads having incorporated therein a plasticizer mixed with or dissolved in an oil very readily undergo stretching when the threads are twisted under the influence of the steam and moisture. The amount of stretch may be measured by comparing the original threaddenier with the final thread denier (after untwisting). It has been found that when a cellulose acetate thread is crepe twisted by the new process involving the treatment of the same with a plasticizer-oil creping aid and steaming during twisting so as to produce a crepe thread of good strength and creping properties, the denier of the resultant thread is, in general, owing to imparted stretch, less and even substantially less than if the thread is simple crepe twisted without such treatments.

The stretch imparted to the filaments of the thread during the twisting operation may, for

example, be of the order of -25% of their original length, and particularly Ill-20%. For ex- 5- ample, the stretching may be such that the denier of the crepe twisted thread is from 95 to 115%, 120% or 125% or more, and particularly 100 to 110% of that of the thread before crepe twisting, especially in case of threads having an original denier of 200 or less. In the case of heavier threads, i. e. those having a denier above 200, the denier increase may be greater and still good crepe effects attained.

The degree of twist applied in accordance with the new process may vary, within wide limits. A feature of the process is that it enables a very high degree of twist to be applied without such a great weakening of the thread as is invariably experienced when cellulose acetate crepe threads are prepared without steaming in the presence of plasticizer-oil aids. The process also enables the use of a reduced number .of turns per inch' to produce the same type of crepe from prior processes. The process, moreover, permits of the insertion of twists which are impossible of attainment without the steaming in the presence of a plasticizer-oil aid, owing to the breakage of the thread. This is important since it enables crepe fabrics having very pronounced crepe effects to be produced. The crepe figure can be regulated according to requirements. The degree of twist desirable in any particular case depends upon a number of factors, including theprecise eflects required, and the denier and number of filaments in the thread. For example, threads of 150 denier may be twisted to about 55 to 75 or more turns per inch, while 100 denier threads may be twisted to about 60 to 100 or more turns per inch. Proportionate twists may be used in case of threads of other deniers.

By the new process highly twisted cellulose acetate crepe threads may be produced in which the filaments are extremely closely packed. As appears from a microscopic examination of the cross-sections of yarns twisted in accordance with this invention, the filaments are squeezed together into substantially as close contact as possible, causing some distortion of the crosssection of at least some of the filaments thereof.

The filaments, however, are not stuck together nor packed togetherand can be separated upon untwisting into individual filaments. The threads produced in accordance with the present invention have been measured and in some instances have a specific gravity of at least 85% of that of a solid thread.

,While this invention enables production of threads which yield satisfactory crepe effects without a special treatment other than the twisting of the thread while it contains a plasticizeroil creping agent in the presence of a steaming treatment characteristic of the process, other devices and treatments may, if desired, be employed further to improve the properties of the crepe threads and/or fabrics produced therefrom. For example, crepe threads, that have the plasticizer-oil dispersed in the filaments, maybe sized at any suitable stage of their manufacture, for example, in the course of winding on to a bobbin from which twisting is effected. In this connection, particular mention may be made of sizing'materials selected in accordance with the considerations laid down ,in British Patent No.

348,589. For example. a casein, egg albumen, or.

other size which is not very readily removed by aqueous treatments, may be employed. Another size which may be employed is a drying oil, if-

desired, one which has been only partially oxidized, e. g. boiled or blown linseed oil.

The highly twisted crepe threads may be incorporated in the fabrics in various ways, for example, the Weft alone may be wholly or partially composed of such threads or the warp may also contain them. Valuable fabrics may be produced by employing in the warp, threads of relatively low twist and in the weftboth crepe threads having a left-hand twist and crepe threads having a right-hand twist, pairs of threads of left-hand twist alternating with pairs of threads of right-hand twist.

If desired, the cellulose acetate crepe threads may be associated in the fabrics with highly twisted crepe threads of other materials, e. g. of natural silk or regenerated cellulose, or threads of artificial silk produced by other processes. Where the fabrics contain threads of low twist these may be wholly of cellulose acetate or wholly or in part of other materials, e. g. natural silk or regenerated celluose.

- Fabrics containing highly twisted crepe threads prepared in accordance with this invention may be scoured in a cold bath to remove a part or all the pasticizer in the creping agent or aid employed during the twisting operation, if the removal thereof is necessary, and then subsequently scoured, for example, in the manner adopted in connection with fabrics comprising highly twisted yarn of natural silk. Enhanced crepe effects may be obtained by employingscouring or other aqueous crepe baths at or near the boiling point. The fabric made in accordance with this invention may be caused to crepe by immersing the same in a bath, containing up to 10 grams or more per litre of soap, for instance, good results being obtained at C. to C. However, by employing certain percentages of plasticizer, the temperature of the creping bath may be considerably lower. The period of treatment in the heated bath may be from about 1 to 30 minutes or more. v

An important characteristic of fabrics exhibiting crepe effects produced in accordance with this invention, such as flat crepes with or without fancy figures, alpaca crepe, etc., is that unlike similar crepe fabrics heretofore produced, they do not shrink substantially when washed or otherwise treated with aqueous liquids, nor do they tend to develop spots when subjected locally (such as by rain) to aqueous liquids. Therefore, garments or other articles made of such fabric may be laundered in the ordinary way without recourse to dry cleaning.

As an illustration in describing this invention and not as a limitation, the following example is given: I

- I Example A yarn of cellulose acetate, having a denier of about to 160, is caused to contact with a furnishing device which applies thereto a creping agent or aid containing between 50 and 60 parts of dibutyl phthalate and 60 to 50 parts of castor oil. The amount of this agent applied to the yarn is between 1% and 3% based on the weight of the yarn. This yarn is twisted to a crepe thread in the presence of steam such that approximately 65 to 75 turns per inch are inserted thereto. The threads are woven to a fabric and the fabric treated in a hot bathmaintained at about 98, C. for a period of about 10 minutes and the fabric produced has a heavy crepe effect, is exceptionally uniform in pebble and shrinkage and is strong.

While this invention has been described in particular connection with cellulose acetate, it is applicable for use with yarns or threads made of other organic derivatives of cellulose, such as cellulose formate, cellulose propionate, cellulose butyrate, or other organic esters of cellulose, or cellulose ethers such as methyl cellulose, ethyl cellulose and benzyl cellulose.

It is to be understood that the foregoing detailed description is merely given by way of illustration and many alterations may bemade therein without departing from the spirit of our invention.

Having described our invention; what we desire to secure by Letters Patent is:

1. Process for the production of highly twisted crepe thread of filaments of an organic derivative of. cellulose, which comprises incorporating with the thread a creping agent or aid containing dibutyl phthalate and a vegetable oil, steaming the thread and crepe twisting the thread of filaments while the thread is subjected to the action of the steam.

2. Process for the production of highly twisted crepe thread of filaments of cellulose acetate, which comprises incorporating with the thread a creping agent or aid containing dibutyl phthalate and a vegetable oil, steaming the thread and crepe twisting the thread of filaments while the thread is subjected to the action of the steam..

3. Process for the production of highlytwisted crepe thread of filaments of cellulose acetate, which comprises incorporating with the thread a creping agent or aid containing dibutyl phthalate and olive oil, steaming the thread and crepe twisting the thread of filaments while the thread is being steamed.

4. Process for the production of highly twisted crepe thread of filaments of cellulose acetate, which comprises incorporating with the thread a creping agent or aid containing dibutyl phthalate and castor oil, steaming the thread and crepe twisting the thread of filaments while the thread is being steamed.

5. Process for the production of highly twisted crepe thread of filaments of an organic derivative of cellulose, which comprises coating the thread with from 1 to 3% based on the weight of the thread of a creping agent containing parts of dibutyl phthalate and 50 parts of a vegetable oil, steaming the thread, and crepe twisting the thread of filaments while the thread is being steamed.

6. Process for the production of highly twisted crepe thread of filaments of cellulose acetate, which comprises coating the thread with from 1 to 3% based on the weight of the thread of a creping agent containing parts of dibutyl phthalate and 40 parts of a vegetable oil, steaming the thread and crepe twisting the thread of filaments while the thread is being steamed.

CAMILLE DREYFUS. WILLIAM WHITEHEAD. 

